Flame hardener

ABSTRACT

A torch-ring-type flame hardener is provided in a plurality of annular plates which are cooperatively milled such that inner unobstructed annular gas and quench water outlets are provided when the plates are assembled. The flame hardener may be mounted to encircle a cylindrical object and to guidingly seat on the object as the object is axially rotated.

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United States' Patent s T. N E M A .3 m m mm IMS n w IT.. N U M [72| Inventors lngwald L. Ramberg;

John L. Benn; Fritz Schreder, all ol King County, Wash.

hardener may be mounted to encircle a cylindrical object and to guldmgly seat on the object as the object |s axially rotated PAENnn JUL am SHEET 1 UF 3 G R m E R o m Mm ANEW RNR H N L w C 1 D S N l- Z N www mim BY gap Q m,'f1"q ATTORNEYS PATENTEUJUL 619m 3,591,154

SHEET 2 0F 3 INGWA LD L. RAMBERG JOHN L.BENN FRITZ SCHREDER INVENTORS ATTORNEYS PATENTEUJUL msn 3,591,154

snm 3 nr 3 INGWALD L. RAMBERG JOHN L. BENN FRITZ SCHREDER INVENTORS ATTORNEYS FLAME HARDENER This invention relates to flame hardeneis of the torch type for heat treating metal objects. More particularly, this invention relates to such flame hardeners which employ a torch ring adapted to encircle an object to be heat treated and which are adapted to impart relative motion between the torch ring and the object such that the heat-treating torch fully traverses the object. Torch ring flame hardeners proposed heretofore have provided a plurality of flame jets and water quenching jets on the object to be heat treated.

ln some instances, either the torch ring or the object is mounted to permit both relative rotation and linear movement between the two such that the flame and water jets sequentially impinge on the object in a helical pattern. ln these instances, the result has been to leave bands of unequally treated material.

ln other instances, the flame jets are arranged around the torch ring in a manner intended to produce a flame sheet composed ofthe individual jets and directed to impinge on the object uniformly. ln these other instances, the jet apertures must be very small and very closely spaced to provide a uniform composite flame sheet, which as a practical matter can only be accomplished by incorporating the jet apertures into the torch ring. Consequently, the jet apertures are easily fouled or plugged by the products of combustion, resulting in the production of a nonuniform flame sheet in the vicinity of the fouled apertures.

Furthermore, the high-temperature flame jets cause erosion of the jet apertures which necessitates periodic repair or replacement of the jet apertures. lf the jet apertures are incorporated into the torch ring, as by perforating the torch ring, aperture erosion can only be corrected by replacing at least the torch ring section containing the jet apertures.

In addition to the difficulties in attaining and maintaining sheet uniformity and in preventing and correcting flame jet aperture fouling and erosion, torch ring flame hardeners proposed heretofore have not satisfactorily provided for centering the object to be heat treated relative to the torch ring. This problem is particularly acute when the object to be heat treated is considerably longer than the thickness of the torch ring and substantial relative movement between the two must occur to work the entire length of the object. If centering of the two is not uniformly maintained over the entire length of 45 the object, the flame sheet will not uniformly impinge on the object even though the flame sheet initially may be uniformly fonned at the flame jets.

A primary object of the present invention is to provide a torch ring flame hardener adapted to provide a continuous flame sheet without employing a plurality of flame jet apertures. Another object is to provide a torch ring structure that is less subject to fouling and erosion and that can be maintained without component replacement. A further object is to provide a torch ring flame hardener adapted to maintain centering between an object to be heat treated and the torch ring.

These and other objects and advantages will become apparent from the following description in conjunction with the accompanying drawings, of which:

FIG. l is a perspective view of a preferred torch ring flame hardener assembly embodying the present invention and adapted to heattreat elongated cylindrical objects;

FIG. 2 is a cross-sectional view of the assembly taken along line 2-2 of FIG. l;

FIG. 3 is a bottom plan view of the torch ring taken along the line 3-3 of FIG. l;

FIG. 4 is an enlarged detail cross-sectional view ofthe torch ring taken along the line 4-4 of FIG. 3;

FIG. 5 is an enlarged plan view detail of a component of the torch ring;

FIG. 6 is a cross-sectional view taken along the line 6-6 of FIG. 5;

FIG. 7 is an elevation view taken along the line 7-7 of FIG. 6;

FIG. 3 is an enlarged partial elevation view of the assembly taken along the line 8 8 of FIG. l; and

FIG. 9 is a cross-sectional view taken along the line 9-9 of FIG. 8.

ln brief, the torch ring flame hardener assembly of thisl invention comprises a torch ring assembly, a torch ring mounting assembly, and a workpiece mounting assembly. The torch ring may be designed to enclose a workpiece for heat treating the exterior surface of the workpiece or to fit within a hollow workpiece for heat treating the interior surface of the workpiece. The torch ring mounting assembly and the workpiece mounting assembly may be so interrelated that the relative positions of the workpiece and the torch ring assembly can be automatically adjusted to maintain centering between the two. For elongated cylindrical workpieces, the torch ring mounting assembly may be provided with means to cause the torch ring assembly to traverse the length of the workpiece. For workpieces having a surface geometry of revolution, the workpiece mounting assembly may be provided with means to cause the workpiece to rotate as the torch ring assembly traverses the length of the workpiece. The flame hardener assembly of FIG. l comprises a torch ring assembly l0, a torch ring mounting assembly 12, and a workpiece mounting assembly 14 and R6.

The torch ring assembly l0 is an annular structure with a circular center opening for a workpiece 18. The annular structure is a composite of four annular plates 22, 24, 26 and 28, all of which have equal inner and outer diameters and are fabricated from high temperature resistant steel. The adjacent surfaces of the plates 24 and 26 are milled to provide an inner periphery annular gas outlet 30 which opens outwardly to the center workpiece opening and which opens inwardly to a contained toroidal gas distribution chamber 32. The adjacent surfaces of the plates 26 and 28 are milled to provide an inner periphery annular quench water outlet 34 which opens outwardly to the center workpiece opening and which opens inwardly to a contained quench water distribution chamber 36. Both distribution chambers 32 and 36 and fluid outlets therefrom, 30 and 34, are continuous and are of uniform cross section throughout so that the respective fluids will be uniformly distributed around the ring and uniformly discharged through the respective outlet, 30 or 34.

To insure uniform gas distribution to the distribution chamber 32, the adjacent surfaces of the plates 24 and 26 are milled to provide an outer annular gas distribution chamber 38 and a plurality of radial passages 40 connecting the two gas chambers 32 and 38. A plurality of gas inlets 42 are threaded into plate 22 in communication with passages 44 that are spaced around the ring and extended through the plates 22 and 26 to the secondary chamber 38. A gas manifold 46 is mounted to the ring and the outlets therefrom are connected to the inlets 42 by tubing 48.

The quench water distribution chamber 36 is not only large enough to supply the desired water sheet from outlet 34 but is also large enough to hold a body of water sufficient to have a significant cooling effect on the adjacent inner regions of plates 26 and 28. Plate 24 is further milled to provide an inner annular cooling chamber 50 large enough to hold a body of water sufficient to have a significant cooling effect on the adjacent inner regions of plates 22 and 24. A quench water inlet 52 is threaded into plate 28 in communication with a passage 54 that is extended through plate 28 to chamber 36. A cooling water inlet 56 is threaded into plate 22 in communication with a passage 58 that is extended through plate 22 to chamber 50. Outer annular cooling water chambers 60 and 62 are milled in plates 24 and 216, respectively, and connected to one another and to chamber 50 by one or more passages 64 extended through plate 26 and one or more passages 66 extended through plate 24, respectively. A cooling water outlet 68 is threaded into plate 28 in communication with a passage 70 extended through plate 28 to chamber 62. Chambers 60 and 62 ,are large enough to hold bodies of water sufficient to have a significant cooling effect on the adjacent outer regions of plates 22, 24, 26 and 28.

Plate 22 is secured to plate 24 by inner and outer rings of capscrews 72 threaded into plate 24. Plates 26 and 28 are secured together and to plates 22 and 24 by an outer ring of capscrews 74 threaded into plate 26 and by a median ring of bolts 76 extended through all of the plates.

The torch ring structure, as thus far described, enables ignited gas and quenching water to impinge on the workpiece as continuous sheets. insofar as the ame sheet is concerned, the continuity of the flame jet aperture 30 eliminates to a substantial degree any tendency toward fouling vis-a-vis the fouling tendency of jets having corner, crevices and minute openings. Furthermore, the continuous flame jet aperture minimizes the possibility of hot spots occuring at the aperture edges that would cause erosion of these edges. Still further, the internal cooling embodied in the structure maintains the plates uniformly cooling all regions except the inner peripheral edge, and prevents the inner peripheral edge portions from overheating.

The assemblage of plates also facilitates reformation of the flame and water apertures by regrinding the adjacent plate surfaces if erosion does occur to a significant degree. Furthermore, by employing intervening plates 26 of different milled thicknesses, the capacity and characteristics of the flame and water apertures can be modified without restructuring the entire torch ring.

Three torch ring roller guide assemblies S are mounted by plate 28 at equispaced intervals. Each roller guide assembly comprises a baseplate 82, a roller-mounting member 84 pivotally mounted by baseplate 82 and a guide roller 86 rotatably mounted by member 84 for rotation about an axis nonnal to the plane of the torch ring. The guide roller periphery extends beyond the adjacent end of baseplate 82 and baseplate 82 is positioned relative to plate 28 such that the guide roller periphery extends into the central opening for contact with the workpiece periphery. The baseplate 82 is provided with an elongated slot 88 through which one of the bolts 76 is extended to adjustably mount the roiler guide assembly on the outer face of plate 28.

Roller 86 is journal mounted on a hollow shaft 90 which is threaded into the exposed face of member 84. Member 84 is retained on a hollow shaft 92 which is journal mounted in baseplate 82. The two hollow shafts 90 and 9?. are offset from one another such that roller 86 can pivot around the axis of shaft 92 as well as rotate about the axis of shaft 9i). Baseplate 82 is bored to provide a passage 83 through which a coiled compression spring 85 extends. The adjacent face of member 84 is provided with an outwardly extending pin 87 that tracks within an arcuate groove 89 in baseplate 82. Spring 85 bears against pin 87 to urge member 84 outward. A second pin 91, upstanding from baseplate 82 on the opposite side of spring 84, prevents member 84 from being pivoted outward beyond a desired limit.

Roller 86 is provided with a hollow cooling water interior with a plurality of water outlet apertures 94 extending outwardly through an end wall 96. Within the interior of roller 86, the shaft 90 is provided with at least one traverse port 98 which opens the shaft interior to the roller interior. Shafts 90 and 92 are connected within member 84 by an internal passage 100. A passage 102 is provided within baseplate 82 to connect shaft 92 with a cooling water inlet 104 threaded into baseplate 82. An inlet line 106 extends from inlet 104 to an outlet 108 which is threaded into plate 28 in communication with cooling water chamber 62 through passage 110.

The torch ring mounting assembly l2 comprises a fiat mounting plate 120, and a double pivot linkage including a pair of plates 122 and 124 mounted at one end to the torch ring, and a bar 126 pivotally mounted at one end between the plates 122 and 124 and at the other end to plate 120. Plates 122 and 124 are superimposed and one is bolted to the exposed face of torch ring plate 22 and the other is bolted to the exposed face of the torch ring plate 28. A pivot pin 128 is mounted by the plates 122 and 124 and extends through bar 126. A second pivot pin 120 is mounted between plate 120 and a mounting block 132 and extends through bar 126.

The midportion of mounting plate is enlarged and includes a cylindrical collar 134 which is axially mounted by a vertical cylindrical mast 136. The rear portion of plate 120 is provided with a threaded bearing 138 through which is extended a vertical jackscrew 140. The rear portion of plate 120 also includes a counterweight 142 to balance the forces acting on plate 120 at the axis of collar 134. The base of mast 136 is mounted to a platform 144 and theV top is guyed by cables 146 extended from the base to a plate 148 secured to the mast top. The jackscrew is secured at the base to'platform 144 and at the top to plate 148 by journal mountings 150 and 152, respectively. The jackscrew is rotated by a reversible motor 139 and drive train assembly 141 mounted on platform 144. To reduce wear on the jackscrew 140, the entire weight of the torch ring and torch ring mounting assemblies may be counterbalanced by a counterweight 154 suspended within mast 136 by a cable 156 reeved around a sheave 158 mounted atop plate 148 secured to mounting plate 120.

Plate 124 protrudes beyond pivot point 128 and is further extended by plate 129 which is bolted thereto. Plate 129 mounts a feed control valve assembly 131 for the gas infeed lines to the manifold 46 such that relative movement between the gas infeed lines and the torch ring, will not occur during movement of the torch ring about pivot points 138 or 130. Mounting plate 120 also mounts a plate 121 containing a clamp 123 adapted to be screwed down onto plate 129 to lock the torch ring in a desired position.

The workpiece mounting assembly includes base spindle mounting 16 positioned on platform 144 and top journal mounting 14 cantilevered from mast 136. The base mounting includes a pedestal atop which the workpiece is positioned and centered by a locking collar 162 for rotation by a drive train 164 from motor 139. The top mounting includes a bearing chuck 166, for a tail spindle 168 contained in a top mounting plate 170. Plate 170 is connected to and cantilevered from a cylindrical collar 172 that encircles mast 136. The upper portion of mast 136 is provided with a recessed gear rack 174 and collar 172 is provided with a pinion 176 which meshes with rack 174 for elevational adjustment of the plate 174B. The rack 174 is recessed to permit the torch ring mounting plate collar 134 to traverse portions ofthe mast 136 containing the rack.

Prior to installing the workpiece, jackscrew 140 is rotated to drive the torch ring down over the pedestal 160 until collar 134 slips over key 141. The torch ring is centered axially of the workpiece spindles and clamped in the centered position by tightening clamp 123. The workpiece top mounting 14 is screwed up out of the way and the workpiece is positioned on the pedestal 160. The top mounting is then screwed down into retaining engagement with the tail spindle 168 of the workpiece. Rotation of jackscrew 140 and workpiece 18 are begun, gas and water flow to the torch ring are commenced, and the gas ejecting from the torch ring is ignited. When the guide rollers 86 contact the workpiece, clamp 123 is loosened so that the torch ring can shift position as required to maintain a centered condition relative to the workpiece as dictated by the rollers 86. Cooling water discharge from the roller ports 94 will spray onto the respective roller guide assembly plates 82 and 84 to cool these plates and will also traverse the outer surface of the respective roller 86 to prevent the roller from seizing or sticking to the workpiece surface. Cooling water discharge from the water outlet 34 will also serve to lubricate the guide rollers. lt is believed that the invention will have been clearly understood from the foregoing detailed description of our now-preferred illustrated embodiment. Changes in the details of construction may be resorted to without departing from the spirit of the invention and it is accordingly myintention that no limitations be implied and that the hereto annexed claims be given the broadest interpretation to which the employed language fairly admits.

The embodiments of the invention in which we claim an exclusive property or privilege are defined as follows:

1. A flame hardener comprising:

distribution chamber opening interconnecting with a continuous water outlet at another interface between lthe assembled plates spaced from said continuous gas outlet; means for supplying gas to said gas distribution chamber; means mounting a workpiece adjacent said torch ring; and guide roller assemblies mounted on said torch ring adapted to guidingly bear against said workpiece to space the torch ring gas outlet uniformly from the adjacent workpiece surface; the guide roller assemblies including a plurality of guide rollers provided with a hollow cooling water interior. `2. The flame hardener of claim l wherein the torch ring is a composite of annular plates having an annular center opening for said workpiece, the plates being of equal inner and outer diameter, further, the meeting adjacent surfaces ofV two of the plates milled to provide a continuous gas outlet which opens to the center opening and which opens inwardly to an internal toroidal gas distribution chamber, and the adjacent meeting surfaces between other of the assembled plates milled to provide a continuous inner annular quench water outlet which opens to the center opening and which opens inwardly to an internal quench water distribution chamber. v

3. The flame hardener of claim l wherein said guide roller assemblies are mounted at equispaced intervals about said torch ring, each assembly including a baseplatc secured to said torch ring, a first hollow shaft mounted in the bascplatc about an axis normal to the plane of the torch ring, a member retained on said first shaft for rotation about said axis, a second hollow shaft offset from said first hollow shaft and parallel thereto, the hollow interiors of said shafts interconnected by a internal passageway in said member, a guide roller whose outer periphery extends into contact with said workpiece mounted for rotation about said second hollow shaft, the guide roller provided with a hollow cooling water interior and a plurality of water outlet apertures, an opening in said second hollow shaft communicating with the hollow interior of said guide roll, means for supplying cooling water to the interior of said guide roller through said first and second hollow shafts, and bias 'means bearing against said guide roll urging it outward into contact with the workpiece; 

1. A flame hardener comprising: a torch ring made up of a composite of several plates cooperatively formed so as to define an internal gas distribution chamber interconnecting a continuous peripheral gas outlet at an interface between the assembled plates, and so as to define an internal quench water distribution chamber opening interconnecting with a continuous water outlet at another interface between the assembled plates spaced from said continuous gas outlet; means for supplying gas to said gas distribution chamber; means mounting a workpiece adjacent said torch ring; and guide roller assemblies mounted on said torch ring adapted to guidingly bear against said workpiece to space the torch ring gas outlet uniformly from the adjacent workpiece surface; the guide roller assemblies including a plurality of guide rollers provided with a hollow cooling water interior.
 2. The flame hardener of claim 1 wherein the torch ring is a composite of annular plates having an annular center opening for said workpiece, the plates being of equal inner and outer diameter, further, the meeting adjacent surfaces of two of the plates milled to provide a continuous gas outlet which opens to the center opening and which opens inwardly to an internal toroidal gas distribution chamber, and the adjacent meeting surfaces between other of the assembled plates milled to provide a continuous inner annular quench water outlet which opens to the center opening and which opens inwardly to an internal quench water distribution chamber.
 3. The flame hardener of claim 1 wherein said guide roller assemblies are mounted at equispaced intervals about said torch ring, each assembly including a baseplate secured to said torch ring, a first hollow shaft mounted in the baseplate about an axis normal to the plane of the torch ring, a member retained on said first shaft for rotation about said axis, a second hollow shaft offset from said first hollow shaft and parallel thereto, the hollow interiors of said shafts interconnected by a internal passageway in said member, a guide roller whose outer periphery extends into contact with said workpiece mounted for rotation about said second hollow shaft, the guide roller provided with a hollow cooling water interior and a plurality of water outlet apertures, an opening in said second hollow shaft communicating with the hollow interIor of said guide roll, means for supplying cooling water to the interior of said guide roller through said first and second hollow shafts, and bias means bearing against said guide roll urging it outward into contact with the workpiece. 